Quaternary phosphorus compounds and method of preparing same



United States Patent 3,206,496 QUATERNARY PHOSPHURUS COMPOUNDS ANDMETHOD OF PREPARING SAME Michael M. Rauhut, Norwalk, Conn, assignor toAmerican Cyanamid Company, New York, N.Y., a corporation of Maine NoDrawing. Filed Sept. 6, 1960, Ser. No. 53,902 9 Claims. (Cl. 260-464)The present invention relates to organophosphorus compounds and methodsof preparing same. More particularly, the instant discovery concernspolymeric phosphonium salts and dimeric phosphonium salts, saidcompounds having, respectively, the following structural configurationsin the molecule wherein R and R in the above formulae represent,respectively, a member selected from the group consisting of substitutedand unsubstituted, branched and straight chain saturated alkyl havingfrom 1 to 12 carbon atoms, and substituted and unsubstituted saturatedcycloalkyl, typical substituents being cyano, phenyl, lower alkoxy,carbalkoxy, carboxy, sulfo, amido, and the like; X is an anion selectedfrom the group consisting of halogen (chlorine, bromine, iodine andfluorine), sulfate, phosphite, phosphate, tetraphenylboride,

Y in said moieties being phenyl, alkyl having 1 to 18 carbon atoms, andalkenyl having 1 to 18 carbon atoms; and n represents a value of atleast 2. When n is 2 the dimeric phosphonium salt has the cyclicstructure of Formula 11', above. Furthermore, R and R in any givenmolecule can be identical or different moieties.

In accordance with the present invention a secondary phosphine havingthe structural formula R (III) wherein R and R have the meaning givenabove, is brought into reactive contact at a temperature in the range of30 C. to 200 C. with a vinyl ester or halide of the formula CH =CHA (IF)wherein A is halogen (bromine, chlorine, iodine and fluorine) and icethe corresponding product of Formula II, above, results. The anions X ofFormulae I and II may be varied con- 'siderably by anion exchange toyield the broad spectrum of products contemplated herein, as will alsobe shown in detail hereinafter.

Typical vinyl esters and halides contemplated herein are: vinylchloride, vinyl bromide, vinyl iodide, vinyl fluoride, vinyl acetate,vinyl 2-ethylhexanoate, vinyl hexahydrobenzoate, vinyl propionate, vinylstearate, and the like.

Pursuant to the instant discovery it has been found that, generally,when the reactants are kept at a temperature in the range of about 30 C.to about 85 C. for at least about 1 hour, say 4 or 5 hours or more, ahomopolymeric di-substituted-ethylenephosphonium salt results having therecurring structural unit of Formula I and an intrinsic viscosity belowabout [1 ]:050.

The rate at which these polymers of Formula I are formed may beincreased by seeding the mixture of reactants with, usually, a smallamount of polymer of Formula I. As evidenced by Example XI, infra, thereaction time may be reduced by percent in certain cases. Generally,however, reaction times greater thanabout one hour are desirable forbest results, with or Without seeding. The amount of accelerator or seedis not critical, since a very minor amount is beneficial and the upperlimit is governed only by practicality of operation.

According to another embodiment of the instantdiscovery, maintaining thereactants contemplated herein at a temperature in the range of about 120C. to about 200 C. for a period of time above about one hour results inthe production, predominantly, of a cyclic dimer having theconfiguration of Formula II, above. The only exceptions to this rule arethe secondary phosphines of the formula above, which contain one or twoZ-cyanoethyl moieties, such as bis(2-cyanoethyl)phosphine. Thesereactants at temperatures in the range of about 50 C. to 200 C. yieldpredominantly the corresponding cyclic dimer II even when heated forperiods of time less than about one hour, as evidenced by Examples I andII, infra. When temperatures below about 50 C. are employed the resulting product comprises the corresponding polymers of Formula I.

It is clear from these assertions, therefore, that as a general rule attemperatures in the range of about 30 C. to about C. the polymer I isthe preponderant product and at temperatures of about C. to about 200 C.the cylic dimer II is the preponderant product, providing, of course,these temperatures are maintained for at least about one hour.

Pursuant to another embodiment of the present invention it has beenfound that at temperatures in the intermediate range, i.e., above about85' C. but below about 120 C., maintained for at least about one hour amixture composed of polymer I and dimer II results. The ratio of thecomponents of this mixture varies considerably, depending upon thereactants. These components may be separated to recover either thepolymer I or the dimer II, or both, as will be evident hereinafter.

Still another embodiment of the present invention is the preparation ofa tertiary phosphine monomer of the formula wherein A is the same as Ain Formula IV, above. A secondary phosphine of Formula III,'-ab,ove, anda vinyl compound of Formula IV, above, are reacted at a temperature inthe range of about 70 C. to about 85 C. for a period of time less thanabout one hour, in the presence of a free radial initiator, and thecorresponding ester or halide monomer is recovered.

This monomeric compound, pursuant to the instant discovery, may beheated as taught hereinabove to a temperature in any of the rangesspecified to produce the corresponding polymer, dimer or mixturethereof, providing, of course, heating is continued for at least aboutone hour. If desired, reaction may be made to take place withoutrecovery of the monomer but in situ. The re maining conditions givenhereinabove for preparation of compounds of Formulae I and II from asecondary phosphine apply equally well to the instant conversion of atertiary phosphine monomer to its corresponding polymer or dimer. I

In the case of the secondary phosphine reactant containing aZ-cyanoethyl moiety, however, its corresponding tertiary phosphinemonomer is generally converted in situ to its corresponding polymer I ordimer II, depending upon temperature.

It has been found, furthermore, that the tendency for the monomerscontemplated herein to convert to their corresponding polymers and/ ordimers may be diminished by the presence of even a small amount of atrialkylphosphine (C -C such a trioctylphosphine, tributylphosphine, orthe like, added before, during or immediately after reaction of thereactants to produce said monomers. The presence of a trialkylphosphinethus facilitates insolation and/ or storage of the monomer whichexhibits a tendency to convert to its corresponding polymer and dimer.

From the above, therefore, it can be seen that upon contacting asecondary phosphine with a vinyl ester or halide under the conditionscontemplated herein the monomer of Formula V, above, is first formed andrecovered, if desired. Recovered or not it may be converted to itscorresponding polymer of Formula I or to its corresponding dimer ofFormula II, or to a mixture thereof. Thus the instant discoveryrepresents a significant contribution to organophosphorus chemistry.

Reaction pursuant to the present invention is made to take place in thepresence of a non-oxidizing free radical initiator, such asdi-t-butylperoxide, 2,2-azodiisobutyronitrile, ultraviolet light, X-rayradiation, or the like. In addition, and if desired, a solvent may beemployed, such as acetonitrile, heptane, dioxane, methyl ethyl ketone,isopropanol, or the like, which solvent is substantally inert under theconditions of reaction with respect to the reactants, the reactionmixure, or the products.

Among the many secondary phosphines suitable for use in the presentinvention are: bis(2-cyanoethyl)-phosphine, bis(3 cyanopropyl)phosphine,methylethylphosphine, bis(2-butoxyethyl) phosphine, dimethylphosphine,diethylphosphine, diisopropylphospine, dibutylphosphine,diisobutylphosphine, didodecylphosphine, dicotylphosphine, bis(2-ethylhexyl) phosphine, bis (2-phenylethyl phosphine,dicyclohexylphosphine, bis(2 methoxyethyl) phosphine,bis(2-carbomethoxyethyl)phosphine, dibenzylphosphine,ethylpropylphosphine, diheptylphosphine, and the like.

The-use of a very substantial excess of either reactant is contemplatedherein, a preferred ratio of reactants being in the range of equimolarproportions up to about moles of the phosphine of Formula III per moleof vinyl acetate, vinyl bromide, or like vinyl compound of Formula IV.

The instant process may be continuous, semi-continuous or batch.Furthermore, suitable results are obtained by operating at atmospheric,sub-atmospheric or superatmospheric pressures.

It should be noted that when using vinyl bromide, vinyl chloride,dimethylphosphine, or other similar volatile reactants, the reaction isbest carried out at super-atmospheric pressures, particularly iftemperatures above 70 C. are employed. This of course, is to preventloss of reactants caused by volatilization.

Generally, with these and like reactants, pressures in the range of 1atmosphere to 30 atmospheres are suitable. However, substantially higherpressures are contemplated herein.

While the anions referred to hereinabove in the product Formulae I andII are preferred, it will be obvious to the skilled chemist that thecarboxylate and halide anions formed as contemplated he-reinabove may beconverted by anion exchange to numerous other anions by conventionalmeans. The examples, infra, further illustrate this point.

The cyclic dimerproducts produced herein are advantageously applied towool, for example, to give protection against injurious insects, such asmoths, and the like. The polymeric products herein are particularlyuseful as anti-static agents for use in textile finishes. These polymersmay be applied to the textile by conventional means. For example, awoven fabric may be dipped into an aqueous, alcoholic or otherappropriate solution of any one of these polymers. Upon retrieving thefabric from the dip, solvent is removed by air drying, or otherwise, andthe resulting polymer-impregnated fabric is thus rendered resistant toannoying static electricity charges.

A mixture of the dimer and homopolymer components, as prepared herein,is likewise useful for wool application and as an anti-static agent; theeffectiveness of the mixture for one use or the other depends upon theratio of its components.

The present invention will best be understood by reference to thefollowing examples which are intended to be illustrative and not undulylimiting to the scope of the invention; for, as will be seenhereinafter, the instant discovery admits of numerous modificationswithin the skill of the art:

EXAMPLE I J ,1,4,4-tetmkis(Z-cyanoethyl) -1,4-diph0sphoniacyclohexanediacetaze ll (NCCHgOH hPH CH =CHOCCH3 CH CH O e 69 6 ll (NCCH CHQ PP(CHzCH CN)2.2OCCHz CHgCHz A solution of 18.9 grams (0.22 mole) of vinylacetate and 1.5 grams (0.01 mole) of 2,2'-azodiisobutyronitrile in 20milliliters of acetonitrile is added dropwise and continuously over aperiod of 20 minutes and with stirring to 28.0 grams (0.20 mole) ofbis(2-cyanoethyl) phosphine which has been warmed to 76 C. under anatmosphere of nitrogen. The reaction temperature is held at 78 C. C.during admixing of reactants and subsequently by intermittent cooling ina water bath and heating when required. After a total time of 45 minutes(including 20 minutes addition time), the resulting opaque, tan, viscousmixture is cooled to room temperature (21 C.23 C.) and stirred into 250milliliters of acetone. Much of the reaction mixture dissolves, leaving22.5 grams (50 percent by weight of theory) of a white crystalline solidhaving a melting point of C.- 15l C.

A portion of this product material is dissolved in boiling isopropylalcohol containing a few drops of water, and the resulting solution isdiluted with 2 volumes of acetone. After standing several days at 10 C.crystals obtain from this solution, which crystals of 1,1, 1,4-tetrakis(2-cyanoethyl) 1,4 diphosphoniacyclohexane diacetate, afterdrying at 53 C. over P 0 melt at 149 C.-150 C.

Analysis.Calculated for C H N O P P, 13.69. Found: P, 13.60, 13.96.

A portion (2 grams) of this product phosphonium acetate is dissolved in100 milliliters of water and treated with a saturated aqueous sodiumbromide solution. The corresponding phosphonium bromide precipitates andis twice recrystallized from water to obtain 1.9 grams of long needlesof 1,1,4,4-tetrakis(2-cyanoethyl)-1,4-diphosphoniacyclohexane dibromidehaving a melting point of 303 C.-304 C.

Analysis.-Calcu1ated for C H Br N P Br, 32.34; P, 12.53. Found: Br,32.81; P, 12.94.

Another small portion of the phosphonium acetate product, above, isdissolved in water and treated with a saturated aqueous potassium iodidesolution. The resulting insoluble iodide is recrystallized from water toobtain an analytical sample of 1,1,4,4-tetrakis(2-cyanoethyl) 1,4-diphosphoniacyclohexane diiodide having a melting point of about 320 C.

Analysis.Calculated for C H I N P I, 43.15; P, 10.53. Found: I, 43.19;P, 10.60.

EXAMPLE II Reaction of bis(2-cyan0ethyl)phosphine with Vinyl Bromide(NCCHgCHzhIH OH CHBr CHzCHg 6B 9 P(OH2CH2CN)2.2BI

CH CI-I A slow stream of vinyl bromide is passed continuously during a30-minute period into a stirred solution of 12.5 grams ofbis(2-cyanoethyl)phosphine and 0.80 gram of 2,2'-azodiisobutyronitrilein 35 milliliters of acetonitrile heated at 80 C. An oil begins toseparate almost immediately. Upon cooling the oil congeals to a whitegum which is separated and extracted with hot water. The extract, whencool, deposits 1.8 grams of crystalline solid having a melting point of300 C.303 C. A mixed melting point with the bromide salt obtained inExample I, above, is not depressed. Furthermore, the infrared spectra ofthe two products are identical.

ea/ Noon omnr CHnCHg 9 P (CHzCHgC O OH)z.2Gl

CHZOHZ 69 (HO O 0 0112011921 Five grams (0.011 mole) of1,1,4,4-tetrakis(2-cyanoethyl)-1,4-diphosphoniacyclohexane diacetateproduced as in Example I, above, is dissolved in 10 milliliters of warmconcentrated HCl. After refluxing 5 minutes the solution congeals to awhite mass. An additional 20 cubic centimeters of concentrated HCl isadded and the mixture refluxed for 1 hour.

After cooling to room temperature, the resulting solid is filtered andwashed with acetone, yielding 5.5 grams of material having a meltingpoint of 259 C.260. C. Recrystallization of this material from about 6percent aqueous HCl, followed by recrystallization from aqueous acetoneproduces 3.7 grams (70 percent by weight of theory) of 1,1,4,4tetrakis(2 carboxyethyl)-l,4-diphosphoniacyclohexane dichloride having amelting point of 280 C.-282 C.

Analysis.-Calculated for C H Cl O P C, 39.93; H, 5.86; P, 12.87; Cl,14.73. Found: C, 39.83; H, 6.05; P, 12.85; Cl, 14.72.

6 EXAMPLE 1v G9 (CIH OCH CHQZP CHgCHg O P (CHzCHgOCfHn) 2.20 CH3 -rCHZCHQ GD ((3 1100 CH CH MP 09 9 P (C 112C 1120 C 4113])221 OHZCHZ Asolution of 12.2 grams (0.05 mole) of bis(2-butoxyethyl)phosphine, 4.5grams (0.05 mole) of vinyl acetate, 0.5 gram (0.003 mole) of22'-azodiisobutyronitrile and 10 milliliters of acetonitrile is warmedat 78 C.-84 C. for 30 minutes. A vigorous exothermic reaction occurs,temperature increases to above 100 C. and the reaction mixture becomesdark brown. The resulting weakly basic solution is combined with 100milliliters of acetone and made acidic (pH 4) with concentratedhydrochloric acid. No precipitation takes place but the color changesfrom brown to light yellow. A saturated aqueous potassium iodidesolution is then added until precipitation is complete. The precipitate(potassium chloride, 4.1 grams) is removed by filtration and thefiltrate concentrated to 10 milliliters under vacuum. The concentrateconsists of a gummy solid and a supernatant liquid consisting of waterand acetic acid. This solid is treated with a mixture of 50 millilitersof acetone and 50 milliliters of ether. A crystalline solid resultswhich is collected by filtration to obtain 3.7 grams of 1,1,4,4-tetrakis(2 butoxyethyl) 1,4 diphosphoniacyclohexane diiodide producthaving a melting point of about 261 C. The iodide is recrystallized oncefrom 50 percent aqueous ethanol and again from 75 percent ethanol toobtain 2.0 grams of pale yellow needles of1,1,4,4-tetrakis(Z-butoxyethyl)1,4-diphosphoniacyclohexane diiodidehaving a melting point of 271 C.273 C.

Analysis.-calculated for C2gH50I204P2: P, 7-97- Found: P, 7.96.

EXAMPLE V 1,1,4,4-telrabutyl-Z-1,4-diph0sph0niacyclohexane diacetate Asolution of 73.4 grams (0.5 mole) of dibutylphosphine, 2.0 grams (0.012mole) of 2,2-azodiisobutyronitrile, and 100 milliliters of heptane iswarmed to 78 C. under an atmosphere of nitrogen, and 43.2 grams (0.5mole) of vinyl acetate is added dropwise and continuously with stirringduring a 15-minute period. The temperature of the mixture is maintainedat 78 C.83 C. during addition by means of intermittent cooling. Theresulting reaction mixture is then stirred at C.85 C. for 1 hour and atC. for 15 minutes. The solvent in the reaction mixture is then removedby distillation under reduced pressure, thus leaving a liquid residuewhich is heated to 95 C. for 30 minutes, during which time vigorousexotherm results and temperature rises to above about C. and whichcongeals to a dark brown tarry mass. Next, three hundred milliliters ofether is added to the mixture and the mixture stirred and refluxed for 1hour. The tarry material dissolves leaving 69.0 grams of a whitecrystalline solid. A portion of the solid is recrystallized from benzenecontaining a small amount of ethanol to obtain an analytical sample of1,1,4,4-tetrabutyl-1,4-diphosphoniacyclohexane diacetate product havinga melting point of 195 C.

Analysis.Calculated for C H O P P, Found: P, 13.65.

This acetate product is highly soluble in water or ethanol but isinsoluble in hot acetone or ethyl acetate.

Ten grams of the product is dissolved in 50 milliliters of water andtreated with a saturated aqueous sodium bromide solution untilprecipitation is'complete. The resulting white product is twicerecrystallized from butanol to obtain an analytical sample of thecorresponding 1,1,4,4 tetrabutyl-l,4-diphosphoniacyclohexane dibromidehaving a melting point of 316 C.319 C.

Analysis.--Calculated for C H Br P P, 12.23. Found: P, 12.20.

This bromide is soluble in Water and absolute ethanol and insoluble inacetone.

-Ano.ther ten-gram portion of the acetate product is dissolved in 50milliliters of water and treated with a saturated aqueous potassiumiodide solution until precipitation is complete. The resulting whitesolid is recrystallized f-rom 500 milliliters of water to obtain 7.8grams of 1,1,4,4-tetrabutyl-1,4-diphosphoniacyclohexane diiodide havinga melting point of 353 C.

Analysis.--Calculated for C H I P I, 43.58. Found: I, 43.31, 43.71.

EXAMPLE VI 1,1,4,4-tetraddecyl-1,4-diph0sph0niacyclohexane diacetate Amixture of 7.0 grams (0.02 mole) of didodecylphosphine, 4.8 grams (0.06mole) of vinyl acetate, 0.5 gram of 2,2-azodiisobutyronitrile, and 10milliliters of acetonitrile is heated at 80 C.-85 C. under an atmosphereof nitrogen for 2 hours. The mixture is then heated an additional 2hours at 130 C. An infrared spectrum of the reaction mixture indicatesthe presence of acetate ion. The addition of 50 milliliters of acetoneprecipitates yellow solid. Three recrystallizations from a mix ture ofethyl acetate and isopropyl alcohol provide a pure sample of1,1,4,4-tetradodecy1-1,4-diphosphoniacyclohexane diacetate.

Analysis.-Calculated for C H O P C, 73.63; H, 12.58; P, 6.78. Found: C,70.14; H, 11.67; P, 6.56.

EXAMPLE VII 1,1,4,4-tetracycl0hexyl-],4-diphosphoniacyclohexane diiodideA mixture of 9.9 grams (0.05 mole) of dicyclohexylphosphine, 4.3 grams(0.05 mole) of vinyl acetate, 0.5 gram of 2,2'-azodiisobutyronitrile,and 110 milliliters of acetonitrile is heated at 80 C.85 C. under anatmosphere of nitrogen for 2 hours. The mixture is then heated anadditional 2 hours at 125 C. The solvent is evaporated under reducedpressure. The solvent is boiled off under an atmosphere of nitrogenuntil the temperature reaches 150 C. An amber liquid results whichiscooled to room temperature (21 C.23 C.). To induce crystallization a50-milliliter quantity of ether is added and the white solid thus formedis filtered and washed with ether. An excess of a saturated aqueouspotassium iodide solution is added to an aqueous solution of a portionof this product-solid. The resulting White solid is filtered 01? andwashed with Water; it has a melting point of about 315 C. Purificationis eifected by boiling the product solid in dimethylformamide,recovering it by filtration, and washing it with acetone. The productthus purified is 1,1,4,4-tetracyclohexyl-1,4- diphosphoniacyclohexanediiodide having a melting point of 317 C.

8 Anralysis.-Calculated for C H I P C, 47.74; H. 7.44; P, 8.79. Found:C, 47.62; H, 7.41; P, 8.50.

EXAMPLE VIII 1,1,4,4-tetrais0butyl-1,4-diphosphoniacyclohexane diiodideA solution of 18.0 grams 0.12 mole) of diisobutylphosphine, 10.6 grams(0.12 mole) of vinyl acetate, and 1.0 gram of ditertiarybutyl peroxidein 20 millilitersof acetonitrile is placed ina-mil'liliterstainless-steel pressure vessel and heated at C.- C. for 10hours. The resulting dark brown, viscous reaction product is treatedwith 75 milliliters of water, and the mixture is extracted with ether.The extract is discarded and the aqueous solution treated with an excessof saturated sodium iodide solution. An insoluble tan solid separatesand is collected. It is washed three times with 25-milliliter portionsof hot acetone and recrystallized from dimethylformamide to obtainrelativelypure phosphonium iodide product, i.e.,1,1,4,4-tetraisobutyl-1-1,4-diphosphoniacyclohexane diiodide.

EXAMPLE IX 1,1,4,4zetraiso butyl-J,4-diph0sphoniacyclohexane diiodide Asolution of 9.0 grams (0.06 mole) of diisobutylphosphine, 5.3 grams(0.06 mole) of vinyl acetate and 10 milliliters of acetonitrile isplaced in a clear quartz tube and irradiated with ultraviolet light for2 hours at 30 C. The reaction mixture is transferred to a flask and thesolvent boiled offuntil the temperature reaches 130 C. The resultingdark brown, viscous mixture is treated with 3 0"milliliters of water,and the mixture extracted with ether. The extract is discarded, and theaqueous solution treated with an excessof saturated sodium iodidesolution. A tan solid separates and-is recrystallized fromdimethylformamide to obtain the product,1,1,4,4-tetraisobutyl-1,4-diphosphoniacyclohexane diiodide.

ll J oo orn n The process of ExamplevV is repeated through the steplllVOlVlIlg the addition of vinyl acetate at 78 C.- 83 C. over a 15minute period except that isopropanol is used as the solvent instead ofheptane. Following said step the reaction mixture is heated at 80 C. for16 hours, whereupon 300 milliliters of ethyl acetate is used and thereaction mixture iscooled to room temperature and filtered. Theresulting filter cake is dried in vacuo and thereby 50 grams ofpolymeric dibutylethylenephosphonrum acetate of melting point 151 C. C.recovered. The polymeric nature of the acetate is confirmed by measuringthe intrinsic viscosity of the" corresponding bromlde salt, the latterbeing obtained by treating a 25 percent aqueous solution of the acetatesalt with aqueous saturated sodium bromide solution and filtering offthe precipitated bromide salt. The intrinsic viscosity of thecorresponding homopolymeric dibutylethylenephosphoium acetatethusfformed determined inwater at 30 C. using a Cannon-Ubbelhodesemi-micro dilution viscometer is [v ]=0.267.

EXAMPLE XI The process of Example X; above, is repeatedexcept that 0.5gram of polymeric dibutylethylenephosphonium acetate, prepared as inExample X, is added to the reaction mixture after the addition of vinylacetate is complete and the reaction time is 4l1ours instead of 16hours. The final polymer has a melting point of 151 C.-154 C. and asimilar intrinsic viscosity.

9 EXAMPLE XII o il -CE L Three grams of a polymericdibutylethylenephosphonium acetate as prepared in Example XI, above, isheated under nitrogen at 160 C.165 C. The solid gradually melts to a redoil. The oil is cooled to room temperature and shaken with a mixture of75 milliliters of benzene and 25 milliliters of water. The benzene phaseis separated and washed twice with 25-milliliter portions of water. Theaqueous solutions are combined, diluted to 150 milliliters with waterand treated with aqueous potassium iodide solution until precipitationis complete. The mixture is filtered to obtain 1.4 grams of white solid.The solid is stirred with 75 milliliters of acetone and filtered toobtain 1.2 grams of the cyclic diphosphonium diiodide, product meltingpoint 337 C.338 C. (with decomposition). A mixed melting point with anauthentic sample as prepared in Example V, supra, is not depressed.

EXAMPLE XIII Polymer from dibutylphosphine and vinyl stearate C4113 '1Pic abomiHo 0 g CIEHHl-ln EXAMPLE XIV1,1,4,4-tetra-n-0ctyl-],4-diphosphoniacyclohexane diiodide A solution of51.6 grams (0.2 mole) of dioctylphosphine, 18.9 grams (0.22 mole) ofvinyl acetate, 1.0 gram of azobisisobutyronitrile, and 250 millilitersof isopropyl alcohol is stirred under nitrogen at 80 C.-83 'C. for 2hours. The solvent is removed under reduced pressure, and the resultingresidue heated at about 120 C. for 2 hours. A red liquid results whichis cooled and dissolved in 100 milliliters of ether, yielding a solutionwhich is extracted repeatedly with ISO-milliliter portions of wateruntil addition of aqueous potassium iodide no longer gives aprecipitate. The resulting extracts are then combined and treated withaqueous potassium iodide until precipitation is complete, and the whitesolid is collected to obtain 26.8 grams of product1,1,4,4-tetra-n-octyl-l,4-diphosphoniacyclohexane diiodide having amelting point of 265 C.-272 C. Two recrystallizations from aqueousethanol increases the melting point of the product to 303 C.304 C.

10 EXAMPLE XV Homopolymeric di-n-octy[ethylenephosphonium iodide Asolution of 51.6 grams (0.20 mole) of redistilled dioctylphosphine(boiling point 110 C.111 C. at 0.2 millimeter mercury), 18.9 grams (0.22mole) of vinyl acetate, 1.0 gram of azoisobutyronitrile and 200milliliters of isopropyl alcohol is heated at 79 C.82 C. with stirringunder nitrogen for 5.5 hours. Thirty minutes after the start 0.5 gram ofpolydi-n-butylethylenephosphonium acetate is added. The resulting yellowreaction mixture is poured into one liter of Water, and the resultingprecipitated solid collected on a coarse sintered glass funnel, Washedwith water, and dried over sulfuric acid to obtain 58 grams of thepolymer, melting point 142 C.144 C. Two reprecipitations from isopropylalcohol with acetone give a product phosphonium acetate polymer meltingat 154 C.156 C.

A solution of 5.0 grams of this phosphonium acetate polymer in 10milliliters of isopropyl alcohol is treated with aqueous potassiumiodide solution. The mixture is poured into 500 milliliters of water andthe resulting solid collected and washed with water. Tworeprecipitations from isopropyl alcohol with water give a product iodidemelting at a temperature over 300 C. and soluble in acetone, benzene,and chloroform. The product is identified as homopolymericdi-n-octylethylenephosphonium iodide by conventional means, i.e., by theuse of a Cannon-Ubbelhode semi-micro dilution viscometer, the intrinsicviscosity of the product being determined in acetone at ambienttemperature (20 C.-25 C.).

EXAMPLE XVI Di-n-bu'tyI-Z-acetoxyethylph0sphine Vinyl acetate (21.5grams, 0.25 mole) is added during 10 minutes to a stirred mixture of36.7 grams (0.25 mole) of di-n-butylphosphine, 1.0 gram ofazoisobutyronitrile, and 75 milliliters of isopropyl alcohol maintainedat 78 C. under nitrogen. The mixture is stirred an additional 30 minutesat C.82 C. The solvent is removed under reduced pressure, and theresulting residue distilled under high vacuum to obtain 35.0 grams ofdi-nbutyl-2-acetoxyethylphosphine, boiling point 62 C.66 C. (0.005millimeter mercury).

Analysis-Calculated for C H O P: C, 62.04; H, 10.85; P, 13.34. Found: C,62.45; H, 10.88; P, 13.13.

EXAMPLE XVII Quaternization of pure di-n-butyl-Z- acetoxyethylphosphineA solution of 5.0 grams of the product of Example XVI, above, in 75milliliters of isopropyl alcohol is refluxed for 24 hours. The solutionis cooled and centrifuged to obtain 3.0 grams (60 percent by weight oftheory) of its corresponding homopolymeric di-n-butylethylenephosphoniumacetate product, melting point 149 C.153 C., the polymeric nature of theproduct being determined by establishing its intrinsic viscosity using aCannon-Ubbelhode semi-micro dilution-viscometer at 25 C.

EXAMPLE XVIII The process of Example XVII, above, is repeated in everyessential respect except that 0.5 gram of the polymer prepared inExample XVII is added to the new reaction mixture; the reaction time forthis repeated experiment is only 3 hours to obtain 3.9 grams (70 percentby weight of theory) of the same product polymer, melting point 149'C.-153 C.

1 1 EXAMPLES XIX-XXI The following table further illustrates the typedimers contemplated herein and the conditions required for theirsolution of the acetate gives the diphosphonium diiodide,

which after recrystallization from water melts at 353 C.Analysis-Calculated for C H I P I, 43.58. Found: 1, 43.71.

production: The filtrate from the diphosphonium diacetate 1s evapo- TABLE I Reactants Example Tempera- Time in Free Radical Initiator SolventProduct Dimer N0. ture, 0. Hours Secondary Phosphine Vinyl DerivativesXIX Bis (2-phenylethyl)- Vinyl aeetate- 130 3 Di-t-butylperoxide Methylethyl 1,1,4,4-tetra(2-phenylethyl)- phosphine. ketone.l,4diphosphoniaeyclohexane diaeetate. XX Bis (Z-carbethcxydo 125 5 X-rayradiation Dioxane 1,1,4,4-tetra(2-earbethoxyethyl) phosphine.ethyl)-1,4-diphosphoniaeyclohexane diacetatc. XXI Bis (2-carbamylethyl)do 145 4 Di-t-butylperoxide. Isopr0panol1,1,4,4-tetra(2-earbamylphosphine. ethyl)-1,4-diphosphoniaeyclohexanediaoetate.

EXAMPLE XXII Quaternization of di-n-butyl-Z-acetoxyethylphosphine Vinylacetate (47.5 grams, 0.55 mole) is added dropwise during minutes to astirred solution of 73.4 grams (0.50 mole) of dibutylphosphine, 2.0grams of a,a-azabisisobutyronitrile (ABN), and 50 milliliters of heptanemaintained at 80 C.85 C. under nitrogen. The solution is stirred at 80C.-85 C. for an additional 30 minutes, and then the temperature israised to 106 C. After several minutes a vigorously exothermic reactiontakes place, and the mixture becomes dark brown. The

rated to a thick syrup under reduced pressure, and the residue dilutedwith 900 milliliters of acetone. A tan solid separates and is collected,washed with acetone and with ether, and dried to obtain 53 grams ofpolydibutylethylene phosphonium acetate, melting point 156 C.- 157 C.

EXAMPLES XXIII-XXXII The following table is intended to show thepreparation by anion-exchange of numerous other typical salts producibleaccording to the teachings of the present invention, all anion-exchangereactions being run at ambient temperature (20 C.23 C.):

TABLE II Reactants Example No. Solvent medium Product Product of ExampleAnion don0r* XXIII V (diaeetate) Chloride-charged anion exchange resinWater l,li,4,iil-ltet riabutyl-l,4-diphosph0niacyelohexane 10 on e. XXIVXXIII AgF do Do,

XXV X Na 4B do Homopolymer of dibutylethylenephosphoniumtetraphenylboride.

XXVI XIV Phosphate-charged anion exchange Methanol1,1,4,4-tetra-n-octyl-1,4-diphosphoniaeyclohexane resin. diphosphate.XXVII XXIII Ag SO Water 1,Iii, ificirabutyl-l,4-diphosphoniaeyelohexane1811 3. e. XXVIII Silver phenyl sulfonate ..d01,1,4,4-tetrakis(ZeyancethyD-l,4-diphosphoniacyclohexanediphenylsulfonate. XXIX Phosphite-charged anion exchange do1,1,4,4-tetrabutyl-1,4-diphosphoniaoyclohexane resin. diphosphite. XXXBis (2-ethy1hexyl) phosphate 1,ligitetrgdidecyl-l,4-diphcsphoniacyclohexanc 1p osp a e. XXXIDioctylphosphinie acid charged anion1,1,4A-tetradodecyl-1,4-diphosphoniaeyclohexane exchange resin. bis(dioctyl)phosphinate. XXXII Oleic acid charged anion exchange1,1,4,4-tetrabutyl-1,4-diphosphoniacyclohexane resin. dioleate.

*The resins n this table are any commercial or conventionalappropriately-charged quaternary ammonium ion exchange resins.

reaction mixture is cooled, diluted with 150 milliliters of ether, andfiltered to obtain 30.0 grams of 1,1,4,4-tetrabutyl 1,4diphosphoniacyclohexane diacetate, melting point about 193 C.l94 C.Recrystallization from benzene containing a few drops of ethanol givesmaterial 0 EXAMPLE XXXIII Diisobutyl-2-acet0xyethylphosphine A solutionof 18.0 grams (0.12 mole) of diisobutylphosphine, 10.6 grams (0.12 mole)of vinyl acetate, and 0.5 gram of a,a-azobisisobutyronitrile in 20milliliters of acetonitrile is heated at C. C. for slightly less thanabout one hour under nitrogen. The solvent is removed under reduce-dpressure, and the residue distilled to give 23.4 grams ofdiisobutyl-Z-acetoxyethylphosphine, boiling point 75 C.84 C. (at 0.35millimeter Hg). A center fraction boiling at 80 C.84 C. (at 0.35millimeter Hg) is analyzed.

Analysis.Calculated for C H O P: C, 62.04; H, 10.85; P, 13.33. Found: C,62.28; H, 11.00; P, 13.38.

EXAMPLE XXXIV 1,1,4,4-Tetmis0butyl-1,4-diphosph0niacyclohexane diz'odideDiisobutyl 2 acetoxyethylphosphine (8.7 grams) is heated at C. for 30minutes under nitrogen. The

resulting dark brown viscous material is dissolved in 5 milliliters ofacetone and then poured into 75 milliliters of water. A small top layerseparates which is extracted with four 25-milliliter portions of ether.The addition of an excess of saturated potassium iodide solution to theremaining aqueous solution precipitates a tan solid. This solid isfiltered, washed with water, and dried. It is washed three times withhot acetone and then recrystallized from dimethylformamide to give 2.4grams of pure product, melting point about 334 C.

Analysis.-Calculatcd for C H I P C, 40.01; H, 7.38; P, 10.31. Found: C,40.40; H, 7.34; P, 10.48.

EXAMPLE XXXV Reaction of bis(2-cyanoethyl) phosphine with vinyl acetatein the presence of tributylphosphine o I (NCOH CHQ PH-I- OH =CHOCiCHs(NC CH CHthP CHzCHzO (ii CH3 rHskP No reaction A solution of 7.0 grams(0.05 mole) of 'bis(2-cyanoethyl)phosphine, 4.7 grams (0.05 mole) ofvinyl acetate, 1.0 gram (0.005 mole) of tributylphosphine, 0.5 gram ofu,aazobisisobutyronitrile and 5 milliliters of acetonitrile is warmed to50 C, with stirring under nitrogen. A moderately vigorous exothermicreaction occurs and the temperature rises to 80 C.85 C. where it ismaintained by cooling. When the exothermic reaction is over (about 4minutes) heat is applied and the temperature maintained at 80 C.-85 C.for 15 minutes, and at 85 C.- 90 C. for 15 minutes. Finally, thesolution is refluxed (102 C.) for 15 minutes. No further reaction takesplace. The infrared spectrum of the reaction mixture indicates that.bis(2-cyanoethyl)-2-acetoxyethylphosphine is the product. Neitheracetate ion or unreacted starting material can be detected.

Clearly, the instant discovery encompasses numerous modifications withinthe skill of the art. Consequently, While the present invention has beendescribed in detail with respect to specific embodiments thereof, it isnot intended that these details be construed as limitations upon thescope of the invention, except insofar as they appear in the appendedclaims The instant application is a continuation-in-part of U8.application Serial No. 790,388, filed February 2, 1959, now abandoned.

14 I claim: 1. A l,1,4,4-tetra-substituted-l,4-disphosphoniacyclohexanesalt of the formula R CHZCHZ R \63/ P P R/ OH2Cg \R wherein R and R,respectively, represent a member selected from the group consisting ofmono-substituted and unsubstituted, branched and straight chainsaturated alkyl having from 1 to 12 carbon atoms, and cyclohexyl, saidsubstituents being selected from the group consisting of cyano, phenyl,lower alkoxy, carbalkoxy, carboxy, sul'fo and amido, and X is an anionselected from the group consisting of halogen, sulfate, phosplu'te,phosphate, tetraphenylboride, 9B (C H 0 oY ll/ OY Y wherein Y in thelast four moieties is selected from the group consisting of phenyl,alkyl having from 1 to 18 carbon atoms, and alkenyl having from 1 to 18carbon atoms.

2. 1,1,4,4 tetrakis(2-cyanoethyl)-1,4-diphosphoniacycylohexanediacetate,

3. 1,1,4,4 tetrakis(2-cyanoethyl)-1,4-diphosphoniacycyohexane dibromide.

4. 1,l,4,4 tetrakis(2-carboxyethyl)-1,4-diphosphoniacyclo'hexanedichloride.

5. 1,1,4,4 tetrakis(2-butoxyethyl) 1,4-dipl1osphoniacyclohexanediiodide.

6. 1,l,4,4 tetrabutyl-1,4-diphosphoniacyclohexane diacetate.

7. 1,1,4,4-tetradodecyl 1,4 diphosphoniacyclohexane diacetate.

8. 1,1,4,4-tetr-acyclohexyl-1,4-diphosphoniacyclohexane 'diiodide.

9. 1,1,4,4 tetraisobutyl-1,4-diphosphoniacyclohexane diiodide.

References Cited by the Examiner FOREIGN PATENTS 673,451 6/52 GreatBritain.

LEON J. BERCOVITZ, Primary Examiner.

MILTON STERMAN, LOUISE P. QUAST,

DONALD E. CZAIA, Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,206,496 September 14, 1965 Michael M. Rauhut It is hereby certifiedthat error appears in the above numbered patent requiring correction andthat the said Letters Patent should read as corrected below.

Column 1, line 57, for "(IE)" read (IV) column 3, line 60, for"dicotylphosphine" read dioctylphosphine column 6, lines 55 to 58, forthat portion of the formula reading CCH read CCH column 8, line 6, for"0,12 mole)" read (0.12 mole) column 9, line 7, second structure, theradical [C H read (C H columns ll and 12, TABLE II, under the headingProduct, third line thereof, for "Do" readl,l,4,4'tetrabutyl1,4-diphosphoniacyclohexane difluoride Signed andsealed this 12th day of April 1966.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

1. A 1,1,4,4 - TETRA-SUBSTITUTED-1,4-DISPHOSPHONIACYCLOHEXANE SALT OFTHE FORMULA